The tragedy had raised fears of a repeat of the bombing of a Russian passenger jet by the Islamic State over Egypt last October that killed all 224 people on board.

An engineer exits from a C-130 HAUP of the Hellenic Air Force, which took part and now is on stand by, in the searching operation of the missing Egypt plane, at the military air base of Kastelli on the southern Greek island of Crete, Friday. (AP Photo)

French Foreign Minister Jean-Marc Ayrault said on Saturday that no theory on the cause of the EgyptAir crash has been ruled out, after revelations of smoke in the cabin minutes before the disaster.

“At this time… all theories are being examined and none is favoured,” he told a news conference after meeting with relatives of passengers who were aboard the doomed A320 flying from Paris to Cairo.

Meanwhile, Smoke alerts were triggered inside the cabin of the ill-fated EgyptAir jet minutes before it plunged into the Mediterranean Sea with 66 people on board, according to new details emerging shortly after human remains, luggage and seats were found by searchers.

Smoke was detected in the toilet and the aircraft’s electrics, just minutes before the signal was lost, according to data published on air industry website the Aviation Herald, which said it had received flight data filed through the Aircraft Communications Addressing and Reporting System (ACARS) from three independent channels.

European Space Agency satellites spotted an oil slick in the area where the flight had vanished – but the organisation said there was no guarantee it was from the plane.

The aircraft had lost contact with radar early Thursday above the Mediterranean Sea about 280 kms from the Egyptian seacoast at 02:30am (local time) as the flight was expected to arrive Cairo Airport at 03:15 am (local time).

The tragedy had raised fears of a repeat of the bombing of a Russian passenger jet by the Islamic State over Egypt last October that killed all 224 people on board.